SetAllPalette procedure

  DECLARATION:  SetAllPalette(var Palette);

      PURPOSE:  Changes all palette colors as specified

         UNIT:  Graph

      REMARKS:  Palette is an untyped parameter.  The first byte of Palette
                indicates the length of the palette.  The remaining bytes
                will replace the current palette colors.  Each color value
                may range from -1 to 15.  A value of -1 will not change the
                previously entry's value.

 RESTRICTIONS:  Must first be in graphics mode.